Air conditioner with cycling fresh air periods

ABSTRACT

In the preferred form, this air conditioner is provided with an electromagnetically opened exhaust air door energized through a bimetal switch connecting in different circuit arrangements to either the portion of the compressor motor circuit controlled by the air conditioner thermostat or the uncontrolled portion to provide periodic opening of the door during either the idle period and the running period or the running period alone or the idle period alone or only at the start of the running period of the compressor.

White tntes tent ,llneohs ll eho 22, 11972 [54] AER @(ENDHTKQNIER Vi/11TH CYQILHNG 2,485,733 10/1949 Hart ..62/262 FRESH AER PEI-11116011138 2,309,224 l/l943 Terry... 2,891,389 6/1959 Tull 1 Inventor: James Jlmbs Dayton, 01110 3,362,465 1/1968 Rector 62/187 73 G 1 M t 1 ti D t 't, 1 Asslgnee gfi 0 0m Comma e ml Primary Examiner-William .l. Wye

Attorney-William S. Pettigrew, Frederick M. Ritchie and Ed- [22] Filed: Apr. 24, 11970 ward P. Barthel [21] Appl. No.: 311,512 [57] ABSTRACT [52] U s CH 62/180 62/262 62/187 In the preferred form, this air conditioner is provided with an 62/158 49/31 62/427 electromagnetically opened exhaust air door energized [51] um Cl lmsd 17/00 through a bimetal switch connecting in different circuit 31 l rangemems to either the portion of the Compressor motor Cir [58] Field of Search 158 cuit controlled by the air conditioner thermostat or the uncontrolled portion to provide periodic opening of the door during [56] References Cited either the idle period and the running period or the running UNITED STATES PATENTS period alone or the idle period alone or only at the start of the 2 332 730 10/1943 Kucher 62/262 running period of the compressor. 2,71 1,080 6/1955 Jewell ..62/262 2 Claims, 7 Drawing Figures fire PAIENTEMEB 2 2 I912 SHEET 1 OF 3 IN ENTOR.

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saw I 0F 3 FAN 78 L I IMOTOR MWW} I 3 Lgfi W/ I l IIIIH'T \T/ W :2 l M I 56 EXHAUST DOOR BIMETAL I j ,3 I ACTUATOR {35 my SWITCH I A L HEAT 8? I I l W M OPERATED "117 -2 I m w 3 W g9? THERMOSTAT *4 ,4 I sIiIFcTOII SWITCH I /COMPRE55OR MOTOR II F'AN w 2- I I MOTOR I I 53 7 I I if I W w I I %o M 86 EXHAUST DOOR {Z5 N C J96 I .3 ACTUATOR I I 'BIMETAL y I I W 595 I SWITCH 2 I 1 HEAT 7 2 I I OPERATED I 4 I I 93 THERMOSTAT I M J SELECTOR SWITCH /cOMPREssOR I MOTOR James jMMw A T TURNFY AIR CONDITIONER WITI-I CYCLING FRESH AIR PERIODS When an air conditioner operates without ventilation, often the air within the room or rooms becomes stale and smoke filled. Most air conditioners provide manually selective noncooling positions in which air is either drawn in or exhausted from the rooms. A few air conditioners are provided with cooling in conjunction with continuous ventilation but this wastes refrigeration and reduces the amount of refrigeration available for the cooling ofthe room or rooms.

It is an object of this invention to provide in an air conditioner, a simple means for periodically opening the ventilating arrangement especially when the least refrigeration is wasted and the cooling ofthe room is least interferred with.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein preferred embodiments ofthe present invention are clearly shown.

IN THE DRAWINGS:

FIG. I is a plan view ofa window-type air conditioning unit illustrating one form of electromagnetically operated door for exhausting room air from the room being cooled;

FIG. 2 is an irregular vertical sectional view taken along the line 2--2 of FIG. 1;

FIG. 3 is a first wiring diagram for the air conditioner as shown in FIGS. land 2;

FIG. 4 is a second wiring diagram for the air conditioner shown in FIGS. 1 and 2 showing a thermostatic control affecting the exhaust door control;

FIG. 5 is a third wiring diagram showing a third air exhaust control system;

FIG. 6 illustrates a fourth wiring diagram showing a fourth type ofdoor control system; and

FIG. 7 illustrates a fifth wiring diagram illustrating a fifth type of ventilating door control.

In FIGS. 1 and 2 my ventilating system is shown applied to the opening of a door in the partition wall of the air conditioner which is so located as to discharge air from the room. However, with a different location the door could be arranged to admit outside air into the room. Since some air conditioners have been provided with both types of doors such as those shown in US. Pat. No. 2,986,0l6, issued May 30, 1961, it is deemed sufficient merely to show a single door for accomplishing the exhausting of the room air since the same system can be used for drawing air into the room by a different location ofthe door as shown in the aforesaid patent.

In FIGS. 1 and 2 there is shown an air conditioner including a support supporting the sealed motor compressor unit 22 which withdraws refrigerant from a tube and fin type evaporator 24 and discharges compressed refrigerant into a fin and tube type condenser 26 from which liquid refrigerant flows through a capillary restrictor tube 28 into the evaporator 24. An irregular partition wall 30 divides the interior of the casing 32 of the air conditioner into an outdoor portion 34 which contains a fan motor 36 and a fan 38 for circulating outside air through the condenser 26 and over the sealed motor compressor unit 22 and an indoor portion 39. On the indoor room side ofthe partition wall 30 is a centrifugal fan 40 driven from the fan motor 36 and located within the centrifugal blower scroll 42 having a front wall 44 provided with an entrance opening 46 directly behind the evaporator 24. The centrifugal fan 40 draws air from the room through the evaporator 24 and discharges the air into a discharge passageway 48 located between the top wall 50 and a horizontal portion 52 of the par" tition wall 30.

This horizontal portion 52 of the partition wall 30 is provided with an exhaust opening 54 communicating with the passage 48 and with the outdoor portion 34. It is provided with upturned flanges. Above this opening 54 is the pivoted exhaust air door 56 which is normally urged to a closing position by the door spring 58. In the closing position the door makes substantial sealing engagement with the upturned flange around the opening 54. To open the door 56 there is provided a cable 60 extending from the door through the eyelets 62, 64 and 66 to the armature 68 of an el-ectromagnet 70 which is fastened to a portion ofthe partition wall 30.

When the electromagnet 70 is energized the armature 6% is pulled in to pull the cable 60 to open the exhaust air door 56 to the position shown in FIG. I. In this position. the door 56 acts as a scoop to scoop the air discharged by the centrifugal fan 40 through the scroll 42 into the: passage 458 to direct air through the opening 54 into the outer portion 34 of the air conditioner for flow to the outside of the room. For a number of reasons, such as simplicity in construction and economy in manufacture, the evaporator 24 is located on the inlet side of the fan 40 so that the air passing through the opening 54 has been drawn from the room and refrigerated by the evaporator 24. Therefore, air which has been cooled by the evaporator 24 is being wasted by being discharged through the opening 54 to the outside atmosphere. Consequently, if it is desired to provide cooling with ventilation, it is desirable to do this when the least amount of refrigeration is being provided by the evaporator and to limit this ventilation to relatively short periods of time. The ventilating arrangements ordinarily provide for the discharge or admittance of about 10-6O percent of the air which is being circulated by the air conditioner.

According to my invention, I have provided five different electrical circuit arrangements for providing periodic limited time opening of the exhaust door. As shown in FIG. 3 the electrical terminal connector 72 has one conductor 74 for the connections to the selector switch 76 which includes a fan switch 78, an exhaust door actuator switch 80 and a motor compressor switch 32 which are connected to operate simultaneously to the four selected positions, namely off, recirculate, cool, and freshen and cool. The compressor motor has one set of terminals connected by conductors 84 to the cool contact (3), to the freshen and cool contact (4) cooperating with the switch 82. The solenoid 70 constituting the exhaust door actuator has one of its terminals connected by the conductor 86 to the freshen and cool contact (4) cooperating with the switch 80. The fan motor 36 has conductors 88 connected to the recirculate contact (2), the cool contact (3) as well as the freshen and cool contact (4) cooperating with the switch 78. In this arrangement in the off position (ll) all three switches 78, 80 and 82 are disconnected from the fan motor 36, the exhaust door actuator 70 and the motor compressor 22.

When these switches are moved to recirculate position, only the switch 78 connects the conductor 74 to the fan motor 36. In the cool position, the switch 78 connects to the fan motor 36 and the switch 82 connects to the compressor motor 22. In the freshen and cool position, all three switches 78, 80 and 82 connect to the freshen and cool terminals thereby providing a connection between the switch 78 and the fan motor 38, a contact between the switch 80 and the exhaust door actuator 70 and a connection between the switch 82 and the compressor motor 22. In all the wiring diagrams the selector switch is the same but in FIGS. 47 the switch positions and terminals are labeled 1, 2, 3, and 4 instead of off, circulate, cool and freshen and cool and these portions bear the same reference characters throughout.

In all the circuits the right terminal of the fan motor 36 connects through the conductor 90 to the second supply conductor 92 connecting with the plug terminal 72. The circuits differ in the provision and location of the air conditioning thermostat and its relation to the exhaust air door switch and the bimetal and heater controls thereof. In FIG. 3 the supply conductor 92 connects through the bimetal heater 94 and the bimetal actuator 96 to the conductor 98 connecting with the second terminal of the compressor motor. The bimetal actuator 96 connects to a normally closed door actuator switch 121 which connects the supply conductor 92 with the conductor 123 connecting with the second terminal of the exhaust door actuator solenoid or electromagnet 70.

Wlth this arrangement, whenever the selector switch 76 is turned to the freshen and cool position. the solenoid 70 will be energized to open the exhaust door 56 to the position shown in FIG. 3. At the same time the compressor motor 22 and the fan 36 will operate to first discharge the air from the fan 40 out of the room. The evaporator 24 at this time will be relatively warm and the air will not be substantially cooled. However, the operation of the compressor motor circulates refrigerant through the system which will gradually cool the evaporator to provide increasing cooling of the air. The relation of the bimetal heater 94 to the bimetal actuator 96 is such that sufficient heat is applied within the period of 1 to 3 minutes to open the door actuator switch 121 thereby to deenergize the electromagnet or solenoid 70 allowing the door 56 to close under the force of the spring 58 to stop the discharge of the air through the outlet opening 54. This arrangement assures that the ventilation takes place at the beginning of the operation of the air conditioner when the least amount of refrigeration will be wasted by the discharge of cooled air from the room.

THE SECOND CIRCUIT, FIGURE 4 In the circuit shown in FIG. 4, the bimetal heater 194 and the air conditioner thermostatic switch 195 are connected in series between the supply conductor 92 and the compressor motor conductor 98. The exhaust door actuator conductor 123 is connected through the normally closed switch 197 with the conductor 98. This door actuator switch 197 is normally closed and is actuated to open position by the bimetal actuator 196 which is heated by the bimetal heater 914 when energized to open within 1 to 3 minutes. With this circuit arrangement the solenoid 70 is deenergized excepting for the initial period of energization of the compressor motor 22.

When the thermostat 194 closes to start a running period of the compressor motor 22, current will flow from the terminal 72 through the conductor 74, the switch 80, when in the freshen and cool position No. 4, through the conductor 86, the solenoid coil 70, the conductor 123, the door actuator switch 197, the thermostat 195, the bimetal heater 1194 and the conductor 92 to the terminal 72. The fan motor 36 will operate continuously during both the running and idle periods of the compressor motor 22 which will also start and run. The operation of the fan motor 36 with the exhaust door open will cause a proportion of the air circulated by the fan 40 to be discharged through the opening 54 in the partition wall portion 52 for discharge outside the room. The operation of the compressor motor 22 will begin to cause evaporation and cooling within the evaporator 24. Within 1 to 3 minutes the bimetal heater 194 will heat the bimetal actuator 196 sufficiently to open the door actuator switch 197 to deenergize the solenoid 70 to reclose the exhaust door. This condition will remain throughout the remainder of the running period which will be terminated by the opening of the thermostat 195.

This thermostat 195 is normally responsive to the temperature of the air drawn from the room prior to contacting the evaporator 24. With this circuit arrangement, the exhausting of a proportion of the air in the room takes place after an idle period of the refrigerating system during which the evaporator 24 warms up nearly to room temperature. The exhausting of the air at the beginning of the running period removes some of the stale and smoke-filled air from the room but little refrigeration is wasted since during the time of this discharge the evaporator is warm and has only a minimum of cooling effect upon the air being circulated and discharged in this initial portion ofthe running cycle.

THE THIRD CIRCUIT, FIGURE In FIG. 5, the bimetal heater 194, the thermostat 195 and the door actuator switch are similar to the corresponding parts in FIG. 4, but the door actuator switch 199, connected in series between the conductors 123 and 98, is different in that it has a set of back contacts 193 which are engaged and closed in the open position of the switch 199 to shunt and deenergize the bimetal heater 194. The bimetal actuator 196 is heated by the bimetal heater 194 upon the closing of the thermostat 195.

blill) During this period both the fan motor 36 and the compressor motor 22 operate and the exhaust door actuator solenoid 70 is energized to open the exhaust air door 56. This causes stale and smoke-filled air to be exhausted through the opening 54 while cooling of the evaporator 24 is begun by the operation of the compressor motor 22. During this starting period, little cooling ofthe air takes place.

Within 1 to 3 minutes, the bimetal heater 194 heats the bimetal actuator 196 sufficiently to move the switch 199 from the position shown in FIG. 5 to a position in which it opens the circuit to the exhaust door actuator solenoid 70 and closes a shunt circuit to deenergize the bimetal heater 194 by closing the contacts 193. This will permit the bimetal heater 194 and the actuator 196 to slowly cool. After this cooling interval, the door actuator switch 199 will return to its normally closed position thereby reenergizing the exhaust door actuator solenoid 70 to reopen the exhaust air door 56 to discharge stale and smoke filled air for a second period. After 1 to 3 minutes the bimetal heater 194 will heat the bimetal actuator 196 sufficiently to reopen the exhaust door actuator solenoid circuit to reclose the exhaust door 56. This intermittent or periodic reopening of the exhaust door 56 will continue until the thermostat opens to terminate the running period or cycle. After the thermostat 195 is warmed sufficiently it will reclose to begin another running period. This particular circuit is especially suitable for installations in which the running cycles are very long since it provides intermittent periods of ventilation throughout the running cycle.

THE FOURTH CIRCUIT, FIGURE 6 The two circuit forms shown in FIGS. 6 and 7 differ from the circuits shown in FIGS. 3-5 in that the switch controlling the exhaust door actuator solenoid 70 connects the conductor 123 effectively to the supply conductor 92 without the intervention of the thermostat switch 195. In FIG. 6, the door actuator switch 297 connects the conductor 123 directly with the conductor 92. This switch 297 is actuated by the bimetal actuator 296 which is heated by the bimetal heater 294 connected between the conductor 92 and the thermostat 195. The switch 297 is normally closed and recloses following a running period within 1 to 3 minutes. This causes the solenoid 70 to be energized a short time after the beginning of each idle period to open the exhaust door 56 for the discharge of stale and smoke-filled air through the opening 54 in the partition wall 52 for flow to the outside of the room.

At the end of the running period the evaporator 24 is cold. It begins to warm up and is warm through the remainder of the idle period so that little refrigeration is wasted at this time. When the thermostat 195 closes, the bimetal heater 294 heats the bimetal actuator 296 and within 1 to 3 minutes the switch 297 will be opened to deenergize the exhaust door actuator solenoid 70 to permit the exhaust door 56 to close and terminate the exhausting of the air for the remainder of the running period of the compressor motor 22. This circuit arrangement provides a much longer ventilation period when the idler periods are long. The long idle periods indicate that the refrigerating requirements are low in proportion to the capability of the air conditioner and greater amounts of ventilation are provided. Short idle periods indicate that the demand for refrigeration is high in proportion to the capacity of the air conditioner and this arrangement provides reduced ventilation during such conditions. Refrigeration is wasted only at the beginning of the idler period after sufficient room cooling has been provided.

THE FIFTH CIRCUIT, FIGURE 7 In FIG. 7 the arrangement is similar to FIG. 6 with the normally closed switch 397 being provided to connect the exhaust door actuator conductor 123 with the circuit portion between the bimetal heater 394 and the air conditioner thermostatic switch 195. This effectively connects to the supply conductor 92 for energizing the exhaust door actuator solenoid 70 to open the exhaust door 56 during substantially the entire idle period of the compressor motor 22 when the selector switch 76 is in the freshen and cool position No. i. The fan motor 36 operates in position i of the switch 78 to discharge stale and smoke filled air through the discharge opening 54 and the outdoor portion 34 for disposal outside the room. The current flow through the exhaust door actuator 70 and the bimetal heater 394 is insufficient to actuate the bimetal actuator 396.

This condition continues when the room conditioner thermostat 195 closes to begin a running period ofthe compressor motor 22 and to periodically energize the bimetal heater 394 to periodically heat the bimetal actuator 396 sufficiently to open the door actuator switch 397 within 1 to 3 minutes. The opening of the switch 397 causes the closing of the back contacts 393 to shunt the bimetal heater 394. This begins a cooling period for the heater 394 and the bimetal actuator 396 which after a few minutes results in the opening of contact 393 and the reclosing of the switch 397 to reconnect with the conductor 123 to reenergize the exhaust door actuator solenoid 70 to reopen the exhaust air door 56 for a short period of time. At the end of this second period of exhausting the bimetal heater 394 will again heat the bimetal actuator 396 sufficiently to open the switch 397 to deenergize the exhaust door actuator solenoid 70 to reclose the exhaust air door 56. This opening and reclosing of the switch 397 in this manner will continue periodically at intervals throughout the remainder of each running period. After the end of each running period the bimetal heater 394 and the bimetal actuator 39 5 will cool and within a few minutes will reclose the door actuator switch 397 to reenergize the exhaust door actuator solenoid 70 to open the exhaust door 56 again to provide another period of ventilation during the remainder of the idler period.

This arrangement not only assures that a large amount of stale air and smoke can be discharged during the idler period but, in addition to the advantages of the circuit shown in FIG. 6, it also assures that periodic ventilation is provided at intervals throughout the running period. The spacing ofthe periods of ventilation during the running period will remain substantially the same so that when the running periods are long there will be more periods of ventilation and the number of ventilating periods will he in proportion to the length of the running cycles. However. the ventilation during the idler periods will he a major factor in providing ventilation.

While the embodiments of the invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted.

i claim:

ii. An air conditioner including a support provided with a partition wall for separating the inside air inside a buiiding from the outdoor air outside thereof, a refrigerating circuit mounted upon said support comprising a motor compressor unit and an outdoor coil located outside said partition wall and an indoor coil located inside said partition wall, fan means for circulating the outdoor air in heat transfer with the outdoor coil and fan means for circulating inside air in heat transfer with the indoor coil, said partition wall being provided with an opening and closure means for closing said opening to provide a limited movement of air through said wall, temperature responsive operating means for starting and stopping said moto compressor unit to provide running and idle periods, wherein the improvement comprises switch means responsive to said operating means for opening said closure means after the end of each running period and for closing said closure means near the beginning of each running period, said switch means for opening and closing being effective after said initial opening and closing of said closure means for repeating said opening and closing of said closure means periodically during the running period to automatically provide a controllable amount of additional air to pass through said opening.

2. An air conditioner including a support provided with a partition wail for separating the inside air inside a building from the outdoor air outside thereof, a refrigerating circuit mounted upon said support comprising a motor compressor unit and an outdoor cor ocated outside said partition wall and an indoor coil located inside said partition wall, fan means for circulating the outdoor air in heat transfer with the outdoor coil and fan means for circulating inside air in heat transfer with the indoor coil, said partition wall being provided with an opening and closure means for closing said opening to provide a limited movement of air through said wall. wherein the improvement comprises electrically operable means for opening said closure means, an electrical circuit for supplying electrical energy to said motor compressor unit and said fan means. switch means for connecting said electrically operable means to said electrical circuit to open said closure means, temper ture responsive operating means for opening said switch means and means responsive to current flow in said circuit for heating said temperature responsive means to effect closing of said closure means.

=t= l i: at a "inn: 

1. An air conditioner including a support provided with a partition wall for separating the inside air inside a building from the outdoor air outside thereof, a refrigerating circuit mounted upon said support comprising a motor compressor unit and an outdoor coil located outside said partition wall and an indoor coil located inside said partition wall, fan means for circulating the outdoor air in heat transfer with the outdoor coil and fan means for circulating inside air in heat transfer with the indoor coil, said partition wall being provided with an opening and closure means for closing said opening to provide a limited movement of air through said wall, temperature responsive operating means for starting and stopping said motor compressor unit to provide running and idle periods, wherein the improvement comprises switch means responsive to said operating means for opening said closure means after the end of each running period and for closing said closure means near the beginning of each running period, said switch means for opening and closing being effective after said initial opening and closing of said closure means for repeating said opening and closing of said closure means periodically during the running period to automatically provide a controllable amount of additional air to pass through said opening.
 2. An air conditioner including a support provided with a partition wall for separating the inside air inside a building from the outdoor air outside thereof, a refrigerating circuit mounted upon said support comprising a motor compressor unit and an outdoor coil located outside said partition wall and an indoor coil located inside said partition wall, fan means for circulating the outdoor air in heat transfer with the outdoor coil and fan means for circulating inside air in heat transfer with the indoor coil, said partition wall being provided with an opening and closure means for closing said opening to provide a limited movement of air through said wall, wherein the improvement comprises electrically operable means for opening said closure means, an electrical circuit for supplying electrical energy to said motor compressor unit and said fan means, switch means for connecting said electrically operable means to said electrical circuit to open said closure means, temperature responsive operating means for opening said switch means, and means responsive to current flow in said circuit for heating said temperature responsive means to effect closing of said closure means. 